Transferring bacteria from old tank to new tank

[Scooter_916]

Hi guys, I currently have a small 2.5 or 3g tank with a few fish that I am wanting to swap over to an older 10g tank.
Long story short I had several (2-10g, 2-20g) tanks as a kid and then got out of the hobby, only to get back into now that my daughter has a fascination with fish and wanted to start a couple tanks for her.
A friend gifted me a tank that she was given by her work when they closed down their office Due to Covid last year. So now I have a small tank with fish that are to big and are in desperate need of a new home.
The tank was given to me with glass marbles and couple plastic plants and a small HOB filter. I dug out some of my old aquarium supplies and swapped out to some of my gravel, a lava rock and went bought a few live plants. I now want to transfer everything to a 10g tank.

I'm reading up about cycling and had a few questions I couldn't find in a search, I don't have much filter media, its a very small HOB filter and only has a sponge in it, around 1" square and 3" long. I was planning on using either my old HOB filter that has the replaceable filter cartridges or use an air driven sponge filter ( or make a Matten filter). so I don't have much filter media to transfer to help in the cycling.

Can I transfer the lava rock form the established tank into the new tank to jump start some bacteria? and while I do that put a rock form the new tank (its been cleaned and disinfected) into the old tank to sort of start colonizing bacteria onto that rock to transfer back after a few days/weeks? Kind of seeding material?

I also want to transfer the gravel into the new tank since that will have bacteria as well.

and i will be needing a lot more plants for the new tank, should I wait till its cycled to plant it, or should I plant now before I start to cycle?

 

[Naughts]

I recommend you start the tank with plants and give them a couple of weeks to establish.
If you transfer the established filter sponge, rocks and gravel at the same time as the fish this should give an instant cycle although you will need to monitor the conditions as a short blip in nitrites may occur.

 

[FishHobby99]

Hi guys, I currently have a small 2.5 or 3g tank with a few fish that I am wanting to swap over to an older 10g tank.
Long story short I had several (2-10g, 2-20g) tanks as a kid and then got out of the hobby, only to get back into now that my daughter has a fascination with fish and wanted to start a couple tanks for her.
A friend gifted me a tank that she was given by her work when they closed down their office Due to Covid last year. So now I have a small tank with fish that are to big and are in desperate need of a new home.
The tank was given to me with glass marbles and couple plastic plants and a small HOB filter. I dug out some of my old aquarium supplies and swapped out to some of my gravel, a lava rock and went bought a few live plants. I now want to transfer everything to a 10g tank.

I'm reading up about cycling and had a few questions I couldn't find in a search, I don't have much filter media, its a very small HOB filter and only has a sponge in it, around 1" square and 3" long. I was planning on using either my old HOB filter that has the replaceable filter cartridges or use an air driven sponge filter ( or make a Matten filter). so I don't have much filter media to transfer to help in the cycling.

Can I transfer the lava rock form the established tank into the new tank to jump start some bacteria? and while I do that put a rock form the new tank (its been cleaned and disinfected) into the old tank to sort of start colonizing bacteria onto that rock to transfer back after a few days/weeks? Kind of seeding material?

I also want to transfer the gravel into the new tank since that will have bacteria as well.

and i will be needing a lot more plants for the new tank, should I wait till its cycled to plant it, or should I plant now before I start to cycle?

I am new to the hobby, but will say I don’t like HOB filters ( I am assuming that means Hang On Back). I had a few that came with tank kits. Switched to sponges, very inexpensive on Amazon. Replacement filters, HOB, were $4, each. Easy to rinse sponge in old tank water. Was getting good parameters on the goldfish tank. Didn’t change filter enough . It bubbled over, making it appear as though the 40 gallon tank suddenly sprung a leak. I was beside myself.

 

[Scooter_916]

I recommend you start the tank with plants and give them a couple of weeks to establish.
If you transfer the established filter sponge, rocks and gravel at the same time as the fish this should give an instant cycle although you will need to monitor the conditions as a short blip in nitrites may occur.

Thank you, I was going to go pick up more plants, and was wanting to attach them to my volcanic rock since there are lots of nooks and crannies to attach the plants to and smaller the holes for the roots to work their way into.

 

[Scooter_916]

I am new to the hobby, but will say I don’t like HOB filters ( I am assuming that means Hang On Back). I had a few that came with tank kits. Switched to sponges, very inexpensive on Amazon. Replacement filters, HOB, were $4, each. Easy to rinse sponge in old tank water. Was getting good parameters on the goldfish tank. Didn’t change filter enough . It bubbled over, making it appear as though the 40 gallon tank suddenly sprung a leak. I was beside myself.

Yeah I'm not a huge fan of the Hang On Back either and will most likely get a sponge filter, I like the ones that suction to the glass and have the two vertical sponges and I have seen a few with a little open space in the bottom to put Bio ceramic media.

once i get this tank going I'm go to start setting up a Neocardina tank with a corner matten filter

 

[AdoraBelle Dearheart]

Thank you, I was going to go pick up more plants, and was wanting to attach them to my volcanic rock since there are lots of nooks and crannies to attach the plants to and smaller the holes for the roots to work their way into.

Sounds good! I agree with naughts advice for transferring the fish, substrate filters etc once plants have had a chance to begin growing, that's how I'd likely do it too.

Only things I'd add are in regard to plants, and HOB filters. For plants, the ones you attach to decor tend to be slow growing plants, like anubius, java fern, mosses etc. These are fine of course, add as many as you'd like! But especially to help with cycling a new tank, even with a seeded cycle, I'd recommend getting a couple of fast growing plants too. Those will help a lot more in terms of sucking up ammonia and making the transition smoother while the bacterial colonies you're trying to transfer continue to grow, and especially if you're thinking of changing filters too.

So personally I'd get some floating plants since they're fast growing ammonia eaters, and fish love the shelter from overhead. Frogbit, salvinia, red root floaters, water lettuce, loads of lovely options there. Plus a fast growing stem plant that you can either plant, or leave to float and grow like mad, also sucking up ammonia. Something like elodea, water wisteria, guppy grass or similar. Fast growing plants can really help so much in terms of water quality and cycling, and saving a tank if there's a sudden source of ammonia like a dead fish or stopped filter.

As for HOB filters, they can be great filters! Some have lots of space for media, you just have to adapt them to suit your needs. Not the replaceable cartridges - those are a con to keep you buying product every month- don't buy any more replaceable cartridges. Use the ones you have until they're falling apart, then gradually replace them with sponge, ceramic media, filter floss, whatever media(s) you plan to use. The HOB on one of my tanks has sections so has bio balls, sponges and filter floss, and does a great job without taking up space in the tank.
Sponge filters are great too, and as you said, many also have compartments you can add bio media to. But since you already have a larger HOB there, you could;

1. Adapt the old, larger HOB to suit your needs. Watch the vid I'll link below for tips, stuff it with whatever media you plan to use, not the replaceable cartridges. Add it to the current tank and run it at the same time as the current smaller HOB, while you're setting up the 10g. You can try squeezing the gunk from the smaller sponge onto the new media in the uncycled HOB, as an attempt to transfer some beneficial bacteria (BB), known as 'seeding' it.

Can I transfer the lava rock form the established tank into the new tank to jump start some bacteria? and while I do that put a rock form the new tank (its been cleaned and disinfected) into the old tank to sort of start colonizing bacteria onto that rock to transfer back after a few days/weeks? Kind of seeding material?

Sure! Every little helps, and since the BB attach to hard surfaces like the substrate, decor etc, you'll be transferring most of your current BB colony by moving the substrate and current filter to the 10g anyway. It won't do any harm to add the cleaned lava rock to the current set up, it'll have grown some biofilm by the time you transfer, so can only help.

Once you're ready to transfer tank contents to the ten gallon, move fish to large covered buckets/storage tote with an airstone. Transfer substrate, decor, both HOB filters, heater etc to new tank. Move fish and airstone to the ten gallon.

While most of the BB colony will have moved to the new tank with the substrate/filters etc, there will still be some of it lost since it's 'new' glass etc, so watch out for a potential brief spike in ammonia or nitrites in the days after the transfer. Best to fast the fish for a day or two, or only feed very very lightly - help reduce ammonia production and give the BB a couple of days to regrow the colony to match the bioload. Do you have a water testing kit?

If ammonia or nitrites do spike, do large water changes as needed. Will usually only be a few days to a week of doing this for the bacteria colony to regrow and the water conditions to stabilise, so don't panic if it happens. But since you've prepared so well, it may go smoothly and not spike at all, especially with the live plants helping. When I transferred my shrimp colony to a new tank (it was an emergency!) it had to be a cleaned, uncycled tank, substrate, plants, decor - only the filter was established. But thanks to lots of live growing stem plants and daily large water changes, it only took a week to ride out the nitrite spike. A while longer for the tank to be fully stable and become established, but it was safe after that week.

Give the ten gallon a couple of weeks running smoothly with both filters, then you can remove the small one, and put the sponge into the larger HOB with the newer media you added to run for a while, or potentially bin that sponge if you like and run only the larger HOB, again, monitoring more closely in case of ammonia/nitrite spikes.

Phew! I hope that helped, and didn't make things more confusing...

 

[Scooter_916]

Sounds good! I agree with naughts advice for transferring the fish, substrate filters etc once plants have had a chance to begin growing, that's how I'd likely do it too.

Only things I'd add are in regard to plants, and HOB filters. For plants, the ones you attach to decor tend to be slow growing plants, like anubius, java fern, mosses etc. These are fine of course, add as many as you'd like! But especially to help with cycling a new tank, even with a seeded cycle, I'd recommend getting a couple of fast growing plants too. Those will help a lot more in terms of sucking up ammonia and making the transition smoother while the bacterial colonies you're trying to transfer continue to grow, and especially if you're thinking of changing filters too.

So personally I'd get some floating plants since they're fast growing ammonia eaters, and fish love the shelter from overhead. Frogbit, salvinia, red root floaters, water lettuce, loads of lovely options there. Plus a fast growing stem plant that you can either plant, or leave to float and grow like mad, also sucking up ammonia. Something like elodea, water wisteria, guppy grass or similar. Fast growing plants can really help so much in terms of water quality and cycling, and saving a tank if there's a sudden source of ammonia like a dead fish or stopped filter.

As for HOB filters, they can be great filters! Some have lots of space for media, you just have to adapt them to suit your needs. Not the replaceable cartridges - those are a con to keep you buying product every month- don't buy any more replaceable cartridges. Use the ones you have until they're falling apart, then gradually replace them with sponge, ceramic media, filter floss, whatever media(s) you plan to use. The HOB on one of my tanks has sections so has bio balls, sponges and filter floss, and does a great job without taking up space in the tank.
Sponge filters are great too, and as you said, many also have compartments you can add bio media to. But since you already have a larger HOB there, you could;

1. Adapt the old, larger HOB to suit your needs. Watch the vid I'll link below for tips, stuff it with whatever media you plan to use, not the replaceable cartridges. Add it to the current tank and run it at the same time as the current smaller HOB, while you're setting up the 10g. You can try squeezing the gunk from the smaller sponge onto the new media in the uncycled HOB, as an attempt to transfer some beneficial bacteria (BB), known as 'seeding' it.


Sure! Every little helps, and since the BB attach to hard surfaces like the substrate, decor etc, you'll be transferring most of your current BB colony by moving the substrate and current filter to the 10g anyway. It won't do any harm to add the cleaned lava rock to the current set up, it'll have grown some biofilm by the time you transfer, so can only help.

Once you're ready to transfer tank contents to the ten gallon, move fish to large covered buckets/storage tote with an airstone. Transfer substrate, decor, both HOB filters, heater etc to new tank. Move fish and airstone to the ten gallon.

While most of the BB colony will have moved to the new tank with the substrate/filters etc, there will still be some of it lost since it's 'new' glass etc, so watch out for a potential brief spike in ammonia or nitrites in the days after the transfer. Best to fast the fish for a day or two, or only feed very very lightly - help reduce ammonia production and give the BB a couple of days to regrow the colony to match the bioload. Do you have a water testing

My bigger HOB wont fit my current tank, it's a small cylindrical 2-3g desk tank.

I will go pick up some plants this week as I think my current plants are dying. I'll be picking up a test kit as well to see where my numbers are for ammonia and nitrate.

My HOB is 20+years old and just found it is leaking at the motor, I'm sure a new o-ring will fix that, I'm actually looking at a a Hygar dual sponge filter with small compartment for bio media under the sponge.

I've been using Seachem Stability that my LFS sold me along with the Prime on the I intial fill.

 

[AbbeysDad]

An aquarium is 'cycled' when there's enough beneficial biology to handle the bio-load. (see Cycling a New Aquarium, a good read for the many ways to cycle an aquarium).
Now some will insist that this takes 6-8 weeks and you must add a bit of pure ammonia every day... But there are better, easier ways. As previously mentioned you might use filter or substrate material from an established tank.

My friend @Byron merely ensures there are plenty of plants, especially fast growing floating plants, that act as ammonia sponges (as they use the ammonia as their nitrogen source).

Many years ago I was watching a Youtube about a pet store that claimed 'instant cycle'. They merely took sponge material from an established tank and 'cleaned' it in the new tank water. (This process was reaffirmed by the Baily Brothers (Tom and Nevil which I explore in the above article)). I have since done this many times and every time with success. Oh the water sure looks ugly for a few hours, but it sure works to jump start the process.
Perhaps the key to this process, or any 'cycling' process is to add new livestock slowly so as not to overload the system with ammonia that the beneficial biology can't handle in a timely fashion.

Of course there are also commercial bottled bacteria products. (see @Byron's article Bacteria in the Freshwater Aquarium and my article Does Bottled Bacteria Really Work) for insights and fascination into the bacteria and microbes that make our aquariums possible.

 

[ClownLurch]

Many years ago I was watching a Youtube about a pet store that claimed 'instant cycle'. They merely took sponge material from an established tank and 'cleaned' it in the new tank water. (This process was reaffirmed by the Baily Brothers (Tom and Nevil which I explore in the above article)). I have since done this many times and every time with success. Oh the water sure looks ugly for a few hours, but it sure works to jump start the process.

Hmmmmm. Interesting. Ive been meaning to ask a question along those lines.
Ive two double barrel air driven sponge filters with the little media compartments underneath in my 120L. I’m probably over filtered but I’d rather that than the alternative.
Ive already helped seed smaller new tanks by using one of the four sponges in my 120L on new double barrelled filters in the smaller tanks and replacing it with a new clean sponge in the 120L. Im now wondering two things:
1/ How many of the four original used sponges could I remove/replace at the same time to reseed new tanks? Without affecting my original tank?
2/ Would squeezing the four used sponges in the clean water of new tanks then returning them to their original tank reduce their effectiveness in the original tank? It seems too much like cleaning them in tap water to me. But if as you say it works then I’ll try it next time, maybe not with four though.

 

[AbbeysDad]

1/ How many of the four original used sponges could I remove/replace at the same time to reseed new tanks? Without affecting my original tank?
2/ Would squeezing the four used sponges in the clean water of new tanks then returning them to their original tank reduce their effectiveness in the original tank? It seems too much like cleaning them in tap water to me. But if as you say it works then I’ll try it next time, maybe not with four though.

It continues to be a hobby MYTH that beneficial bacteria only lives in the filter...
You can 'clean' sponges from an established tank in the new tank water and put them back (as if you had otherwise cleaned them in used tank water OR under the tap). The reason you can do this is that bacteria does not live in the filter alone...but on all 'hard' surfaces in the aquarium, especially on and in the substrate.

Now having written the above, I'll mention again that all of my filters, including the large canister filter on the 110g stock tank, are completely filled with sponge material. Now in the olden days, I was a bit obsessed with keeping things clean using the logic that detritus trapped in a filter decomposes and pollutes the water - so you'd want to clean regularly to get the crud out. HOWEVER, I came to learn that beneficial bacteria and microbes setup housekeeping inside the filter sponges, doing their job to aid in water purification. Cleaning upsets and disrupts this important process. So these days, I only clean filter sponges when the water flow is noticeably reduced, and then typically only clean enough to restore flow. Incidentally, the above is the same reason that I do not disturb my 3"+ sand substrate.

 

[Scooter_916]

Thank you! I plan on moving the substrate from my small desk top to the 10g. how easy does the bacteria come off? will the process of scooping it out scrape off much of the bacteria?

 

[Naughts]

Thank you! I plan on moving the substrate from my small desk top to the 10g. how easy does the bacteria come off? will the process of scooping it out scrape off much of the bacteria?

The bacteria are pretty sturdy. Keep it damp, avoid chlorine (in untreated tapwater) and, ideally, keep it oxygenated.